Method of combating nematodes



United States 3,036,951 METHOD OF COMBATING NEMATODES HansDisselnkiitter, Koln-Poll, and Bernhard Homeycr,

Koln-Stammheim, Germany, assignors to Fariaenfahrikeu BayerAktiengesellschaft, Leverkusen, Germany,

a corporation of Germany No Drawing. Filed July 7, 1959, Ser. No.825,421

Claims priority, application Germany July 22, 1258 3 Claims. (Cl.167-22) The present invention relates to and has as its object compoundsfor combating nematodes and methods for applying same.

Halogenated hydrocarbons such as especially 1,3-dichloropropene,1-chloro-3-bromopropene and 1,2-dibromo-3-chloropropane are best knownfor combating phytopathogenic soil nematodes.

It has now been found that the 1,2-dibromopentane and4,5-dibromopentine-1 have an excellent action on all economicallyimportant plant-damaging nematodes. Compared with the hitherto bestknown 1,2-dibromo-3- chloropropane, the compounds according to theinvention have an essentially better plant tolerance Whilst having atleast the same nematicidal activity thus reducing the time which has tobe elapsed between application and planting of most cultivated plants byhalf or more as against the aforesaid compound even at low temperaturesof 10 and 15 C.

1,2-dibromopentane and 4,5-dibromo-pentine-1 can easily be formulated byknown methods to give liquids or sprays.

Accordingly, the liquid active substance may be applied with the aid ofa soil injector or by spraying, and also harrowed or harked into thesoil. The compounds to be used according to the invention surprisinglyhave also fungicidal action.

The following examples are given for illustrating the invention.

Example 1 Soil infected with phytopathogenic nematodes such asMeloidagyne incognita, Heterodera rostochiensis and Ditylenchus dipsaciwas treated in Mitscherlich pots of litre capacity with4,5-dibromopentine-l in quantities of 5, 10, 15 and 20 ppm. The potswere kept at 24 C. and planted with tomatoes and potatoes or sown withrye after 1 week.

The evaluation of the tests was carried out after 5 weeks. The roots oftomatoes and potatoes were tested as to infestation by galls or cysts.The rye plants were tested with the aid of a modified Baermann funnelmethod on imported rye eels. The degree of efficiency calculatedaccording to the Abbott formula, Journ. Econ. Ent, vol. 18, 1925,265267, is indicated in the following tables.

4,5-DIBROMPENTINE-1 $236,951 Patented May. 29,, l 962 Example 2 5 com!10 ccmJ 15 com, 20 com./ m? m. In? In.

Percent Percent Percent Percent 1,2-D1bromopentane 4O 100 forcomparison: 1,2-Dibromo- B-chloropropane 50 90 100 100 Example 3 Therespective tolerance by plants and the necessary refraining period fromcultivation was ascertained by injecting the two compounds in quantitiesof 10, 20, 30, 40 and 50 cc./sq.m. into each of 12 sq.m.-allotments. Thetemperature in 5 cm. depth of soil varied between 15 and 21 C. After arefraining period from cultivation of 1 to 2 weeks, lettuce, onions andcarrots were sown. The evaluation of plant growth in comparison with theuntreated control was carried out in each case after 4 weeks accordingto the following scheme:

2 means normal plant growth (as in the untreated control) 3 means slightdamage to plant growth 4 means strong damage to plant growth 5 meansvery strong damage to plant growth 10 g./ 20 g./ 30 g./ 40 g./ 50 g./mfi m. m! ml in.

lettuce after 1 week:

4,5-Dibromopentine- 2 2 3 3 4 for comparison-1,2-Dibromo 3chloro-propane 3 3 4 5 5 control 2 2 2 2 2 lettuce after 2 weeks:

4,5-Dibromopentine-1 2 2 2 3 4 for comparison1,2-Dibromo 3 -Clll0l0-propane 2 2 3 4 4 control. 2 2 2 2 2 onions after 1 week:

4,5-Dibromopentine-l 2 3 3 4 5 for comparison-1,2-Dibromo 3 ehloropropane 3 4 4 5 5 control 2 2 2 2 2 onions after 2 weeks:

4,5-Dibromopentine-1 2 2 3 4 4 for comparison1,2-Dibromo -3 chloropropane 2 3 4 5 5 control 2 2 2 2 2 carrots after 1 week:

4,5-Dibromopentine-1. 2 2 2 3 3 for eompariscn1,2-Dibromo 3 chloro pro-4,5-Dibromopentine-1. 2 2 2 2 2 for comparison1,2-Dibromo 3 chloropropane 2 2 2 3 3 control 2 2 2 2 2 We claim:

1. Method of combating nematodes consisting of applying to nematodeinfested soil a member selected from the group consisting of4,5-dibromopentine-1 and 4,5-dibromopentane.

3 1 2. Method of combating nematodes consisting of ap- 2,849,365Youngson Aug. 26, 1958 plying to nematode infested soil4,5-dibromopentine-1. 2,875,118 Turner Feb. 24, 1959 3. Method ofcombating nematodes consisting of ap- 2,947,660 Hofimann Aug. 2, 1960plying to nematode infested SO11 4,5-d1bromopentane. r FOREIGN PATENTS124,387 Australia June 12, 1947 References Cited in the file of thispatent UNITED STATES PATENTS OTHER REFERENCES Leavitt Feb- 4, 9 Parnell:Brit. J. PharmacoL, 1952, vol. 7, pps.

509-533 (page 514 relied on).

2,749,377 Johnson June 5, 1956 2,836,536 Meuli May 27, 1958 10

1. METHOD OF COMBATING NEMATODES CONSISTING OF APPLYING TO NEMATODEINFESTED SOIL A MEMBER SELECTED FROM THE GROUP CONSISTING OF4,5-DIBROMOPENTINE-1 AND 4,5-DIBROMOPENTANE.